Pretty cool discovery. Goes to show we haven't learned everything yet.
Hopefully, scientists can get a robot or camera in there to see what's in it. No hieroglyphics, except for faked ones have been found in the Great Pyramid, so it's hard to say what it was built for, a tomb or otherwise. Many theories have been postulated over the years, some more way out than others, such as it was built by ETs.
"Military men are dumb, stupid animals to be used as pawns for foreign policy."
--Henry A. Kissinger, jewish politician and advisor